freebsd-skq/sys/kern/subr_coverage.c
andrew be20ad6345 Extract the coverage sanitizer KPI to a new file.
This will allow multiple consumers of the coverage data to be compiled
into the kernel together. The only requirement is only one can be
registered at a given point in time, however it is expected they will
only register when the coverage data is needed.

A new kernel conflig option COVERAGE is added. This will allow kcov to
become a module that can be loaded as needed, or compiled into the
kernel.

While here clean up the #include style a little.

Reviewed by:	kib
Sponsored by:	DARPA, AFRL
Differential Revision:	https://reviews.freebsd.org/D18955
2019-01-29 11:04:17 +00:00

238 lines
6.3 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright (C) 2018 The FreeBSD Foundation. All rights reserved.
* Copyright (C) 2018, 2019 Andrew Turner
*
* This software was developed by Mitchell Horne under sponsorship of
* the FreeBSD Foundation.
*
* This software was developed by SRI International and the University of
* Cambridge Computer Laboratory under DARPA/AFRL contract FA8750-10-C-0237
* ("CTSRD"), as part of the DARPA CRASH research programme.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/coverage.h>
#include <machine/atomic.h>
void __sanitizer_cov_trace_pc(void);
void __sanitizer_cov_trace_cmp1(uint8_t, uint8_t);
void __sanitizer_cov_trace_cmp2(uint16_t, uint16_t);
void __sanitizer_cov_trace_cmp4(uint32_t, uint32_t);
void __sanitizer_cov_trace_cmp8(uint64_t, uint64_t);
void __sanitizer_cov_trace_const_cmp1(uint8_t, uint8_t);
void __sanitizer_cov_trace_const_cmp2(uint16_t, uint16_t);
void __sanitizer_cov_trace_const_cmp4(uint32_t, uint32_t);
void __sanitizer_cov_trace_const_cmp8(uint64_t, uint64_t);
void __sanitizer_cov_trace_switch(uint64_t, uint64_t *);
static cov_trace_pc_t cov_trace_pc;
static cov_trace_cmp_t cov_trace_cmp;
void
cov_register_pc(cov_trace_pc_t trace_pc)
{
atomic_store_ptr(&cov_trace_pc, trace_pc);
}
void
cov_unregister_pc(void)
{
atomic_store_ptr(&cov_trace_pc, NULL);
}
void
cov_register_cmp(cov_trace_cmp_t trace_cmp)
{
atomic_store_ptr(&cov_trace_cmp, trace_cmp);
}
void
cov_unregister_cmp(void)
{
atomic_store_ptr(&cov_trace_cmp, NULL);
}
/*
* Main entry point. A call to this function will be inserted
* at every edge, and if coverage is enabled for the thread
* this function will add the PC to the buffer.
*/
void
__sanitizer_cov_trace_pc(void)
{
cov_trace_pc_t trace_pc;
trace_pc = (cov_trace_pc_t)atomic_load_ptr(&cov_trace_pc);
if (trace_pc != NULL)
trace_pc((uint64_t)__builtin_return_address(0));
}
/*
* Comparison entry points. When the kernel performs a comparison
* operation the compiler inserts a call to one of the following
* functions to record the operation.
*/
void
__sanitizer_cov_trace_cmp1(uint8_t arg1, uint8_t arg2)
{
cov_trace_cmp_t trace_cmp;
trace_cmp = (cov_trace_cmp_t)atomic_load_ptr(&cov_trace_cmp);
if (trace_cmp != NULL)
trace_cmp(COV_CMP_SIZE(0), arg1, arg2,
(uint64_t)__builtin_return_address(0));
}
void
__sanitizer_cov_trace_cmp2(uint16_t arg1, uint16_t arg2)
{
cov_trace_cmp_t trace_cmp;
trace_cmp = (cov_trace_cmp_t)atomic_load_ptr(&cov_trace_cmp);
if (trace_cmp != NULL)
trace_cmp(COV_CMP_SIZE(1), arg1, arg2,
(uint64_t)__builtin_return_address(0));
}
void
__sanitizer_cov_trace_cmp4(uint32_t arg1, uint32_t arg2)
{
cov_trace_cmp_t trace_cmp;
trace_cmp = (cov_trace_cmp_t)atomic_load_ptr(&cov_trace_cmp);
if (trace_cmp != NULL)
trace_cmp(COV_CMP_SIZE(2), arg1, arg2,
(uint64_t)__builtin_return_address(0));
}
void
__sanitizer_cov_trace_cmp8(uint64_t arg1, uint64_t arg2)
{
cov_trace_cmp_t trace_cmp;
trace_cmp = (cov_trace_cmp_t)atomic_load_ptr(&cov_trace_cmp);
if (trace_cmp != NULL)
trace_cmp(COV_CMP_SIZE(3), arg1, arg2,
(uint64_t)__builtin_return_address(0));
}
void
__sanitizer_cov_trace_const_cmp1(uint8_t arg1, uint8_t arg2)
{
cov_trace_cmp_t trace_cmp;
trace_cmp = (cov_trace_cmp_t)atomic_load_ptr(&cov_trace_cmp);
if (trace_cmp != NULL)
trace_cmp(COV_CMP_SIZE(0) | COV_CMP_CONST, arg1, arg2,
(uint64_t)__builtin_return_address(0));
}
void
__sanitizer_cov_trace_const_cmp2(uint16_t arg1, uint16_t arg2)
{
cov_trace_cmp_t trace_cmp;
trace_cmp = (cov_trace_cmp_t)atomic_load_ptr(&cov_trace_cmp);
if (trace_cmp != NULL)
trace_cmp(COV_CMP_SIZE(1) | COV_CMP_CONST, arg1, arg2,
(uint64_t)__builtin_return_address(0));
}
void
__sanitizer_cov_trace_const_cmp4(uint32_t arg1, uint32_t arg2)
{
cov_trace_cmp_t trace_cmp;
trace_cmp = (cov_trace_cmp_t)atomic_load_ptr(&cov_trace_cmp);
if (trace_cmp != NULL)
trace_cmp(COV_CMP_SIZE(2) | COV_CMP_CONST, arg1, arg2,
(uint64_t)__builtin_return_address(0));
}
void
__sanitizer_cov_trace_const_cmp8(uint64_t arg1, uint64_t arg2)
{
cov_trace_cmp_t trace_cmp;
trace_cmp = (cov_trace_cmp_t)atomic_load_ptr(&cov_trace_cmp);
if (trace_cmp != NULL)
trace_cmp(COV_CMP_SIZE(3) | COV_CMP_CONST, arg1, arg2,
(uint64_t)__builtin_return_address(0));
}
/*
* val is the switch operand
* cases[0] is the number of case constants
* cases[1] is the size of val in bits
* cases[2..n] are the case constants
*/
void
__sanitizer_cov_trace_switch(uint64_t val, uint64_t *cases)
{
uint64_t i, count, ret, type;
cov_trace_cmp_t trace_cmp;
trace_cmp = (cov_trace_cmp_t)atomic_load_ptr(&cov_trace_cmp);
if (trace_cmp == NULL)
return;
count = cases[0];
ret = (uint64_t)__builtin_return_address(0);
switch (cases[1]) {
case 8:
type = COV_CMP_SIZE(0);
break;
case 16:
type = COV_CMP_SIZE(1);
break;
case 32:
type = COV_CMP_SIZE(2);
break;
case 64:
type = COV_CMP_SIZE(3);
break;
default:
return;
}
val |= COV_CMP_CONST;
for (i = 0; i < count; i++)
if (!trace_cmp(type, val, cases[i + 2], ret))
return;
}